2nd Generation Specific 1986-1992 Discussion

AFTERMARKET TACH

Old Apr 28, 2009 | 03:19 PM
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on a aftermarket tach (vdo guage) do you set the guage to run of the 6 cylinder setting?
Old Apr 28, 2009 | 04:06 PM
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i havnt had the joy of playing with the VDO unit yet, but i have always set my autometer to 4 cylender
Old Apr 28, 2009 | 05:31 PM
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yeah its a 4 cylinder.
Old Apr 29, 2009 | 02:04 PM
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COOL i dont have to change that from the engine swap!!!
Old Apr 30, 2009 | 08:37 AM
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Originally Posted by RX200013B' post='921117' date='Apr 29 2009, 01:04 PM
COOL i dont have to change that from the engine swap!!!




what if the stock guage cluster is from a mazda and is a 4 banger, wouldn't it work the same as setting a VDO tach?
Old Apr 30, 2009 | 09:40 AM
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Originally Posted by RX200013B' post='921143' date='Apr 30 2009, 06:37 AM
what if the stock guage cluster is from a mazda and is a 4 banger, wouldn't it work the same as setting a VDO tach?


2 rotor fires every 180 degrees, just like a 4 cylinder piston engine.



so yes it would work the same setting, in fact most new cars use a 4 cylinder tach, and just have the ecu output that signal no matter what engine its running
Old May 3, 2009 | 02:10 PM
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The Rotary fires 6 times per one RPM of the rotors (2 rotors x 3 sides). But since the Rotors travel at 1/3 the speed of the crank. The actual RPM you are measuring is the crank speed . Since the Tach signal is reading a single rotor is works out to be 1 pulse = 1 RPM @ the crank) or 1:1 which is the same as a 4 cylinder (4 stroke) motor 1:1.



4 cylinders each firing 4 times per 4 revolutions of the crank, or 1:1
Old May 3, 2009 | 03:57 PM
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Originally Posted by dac' post='921246' date='May 3 2009, 12:10 PM
The Rotary fires 6 times per one RPM of the rotors (2 rotors x 3 sides). But since the Rotors travel at 1/3 the speed of the crank. The actual RPM you are measuring is the crank speed . Since the Tach signal is reading a single rotor is works out to be 1 pulse = 1 RPM @ the crank) or 1:1 which is the same as a 4 cylinder (4 stroke) motor 1:1.



4 cylinders each firing 4 times per 4 revolutions of the crank, or 1:1


a 4 cylinder 4 stroke engine fires once every 180 degrees of the crankshaft, same as a 2 rotor rotary.



6 cylinder 4 stroke is ever 120, like a 3 rotor
Old May 6, 2009 | 02:09 PM
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And what's wrong with the factory tach? Does it not measure RPM's correctly? or do after market large over kill tach's add more horse power? Or give you experience points in a InitialD JDM realm? Sorry I'm playing on the last two... Seriously why reinvent the wheel? I am just curious.
Old May 7, 2009 | 12:30 PM
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Originally Posted by CPUBUGS' post='921374' date='May 6 2009, 01:09 PM
And what's wrong with the factory tach? Does it not measure RPM's correctly? or do after market large over kill tach's add more horse power? Or give you experience points in a InitialD JDM realm? Sorry I'm playing on the last two... Seriously why reinvent the wheel? I am just curious.






the factory tach is out a mazda b2000 w/ carbed 4 cylinder!!!



i will NOT gain any horsepower?



i dont play video games,, "childs play" i have better things to do!!!



thanks for the smartASS comments!



go back to your intialD realm

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